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1.
BMC Genomics ; 25(1): 444, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711017

RESUMO

BACKGROUND: Normalization is a critical step in the analysis of single-cell RNA-sequencing (scRNA-seq) datasets. Its main goal is to make gene counts comparable within and between cells. To do so, normalization methods must account for technical and biological variability. Numerous normalization methods have been developed addressing different sources of dispersion and making specific assumptions about the count data. MAIN BODY: The selection of a normalization method has a direct impact on downstream analysis, for example differential gene expression and cluster identification. Thus, the objective of this review is to guide the reader in making an informed decision on the most appropriate normalization method to use. To this aim, we first give an overview of the different single cell sequencing platforms and methods commonly used including isolation and library preparation protocols. Next, we discuss the inherent sources of variability of scRNA-seq datasets. We describe the categories of normalization methods and include examples of each. We also delineate imputation and batch-effect correction methods. Furthermore, we describe data-driven metrics commonly used to evaluate the performance of normalization methods. We also discuss common scRNA-seq methods and toolkits used for integrated data analysis. CONCLUSIONS: According to the correction performed, normalization methods can be broadly classified as within and between-sample algorithms. Moreover, with respect to the mathematical model used, normalization methods can further be classified into: global scaling methods, generalized linear models, mixed methods, and machine learning-based methods. Each of these methods depict pros and cons and make different statistical assumptions. However, there is no better performing normalization method. Instead, metrics such as silhouette width, K-nearest neighbor batch-effect test, or Highly Variable Genes are recommended to assess the performance of normalization methods.


Assuntos
Análise de Célula Única , Análise de Célula Única/métodos , Humanos , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/normas , Análise de Sequência de RNA/métodos , Transcriptoma , Algoritmos , RNA-Seq/métodos , RNA-Seq/normas , Animais
2.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473791

RESUMO

Androgenetic alopecia is a highly prevalent condition mainly affecting men. This complex trait is related to aging and genetics; however, multiple other factors, for example, lifestyle, are also involved. Despite its prevalence, the underlying biology of androgenetic alopecia remains elusive, and thus advances in its treatment have been hindered. Herein, we review the functional anatomy of hair follicles and the cell signaling events that play a role in follicle cycling. We also discuss the pathology of androgenetic alopecia and the known molecular mechanisms underlying this condition. Additionally, we describe studies comparing the transcriptional differences in hair follicles between balding and non-balding scalp regions. Given the genetic contribution, we also discuss the most significant risk variants found to be associated with androgenetic alopecia. A more comprehensive understanding of this pathology may be generated through using multi-omics approaches.


Assuntos
Alopecia , Folículo Piloso , Masculino , Humanos , Genômica , Envelhecimento , Estilo de Vida
3.
Int J Mol Sci ; 24(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37958990

RESUMO

It has been suggested that the neuro-visceral integration works asymmetrically and that this asymmetry is dynamic and modifiable by physio-pathological influences. Aminopeptidases of the renin-angiotensin system (angiotensinases) have been shown to be modifiable under such conditions. This article analyzes the interactions of these angiotensinases between the left or right frontal cortex (FC) and the same enzymes in the hypothalamus (HT), pituitary (PT), adrenal (AD) axis (HPA) in control spontaneously hypertensive rats (SHR), in SHR treated with a hypotensive agent in the form of captopril (an angiotensin-converting enzyme inhibitor), and in SHR treated with a hypertensive agent in the form of the L-Arginine hypertensive analogue L-NG-Nitroarginine Methyl Ester (L-NAME). In the control SHR, there were significant negative correlations between the right FC with HPA and positive correlations between the left FC and HPA. In the captopril group, the predominance of negative correlations between the right FC and HPA and positive correlations between the HPA and left FC was maintained. In the L-NAME group, a radical change in all types of interactions was observed; particularly, there was an inversion in the predominance of negative correlations between the HPA and left FC. These results indicated a better balance of neuro-visceral interactions after captopril treatment and an increase in these interactions in the hypertensive animals, especially in those treated with L-NAME.


Assuntos
Captopril , Hipertensão , Ratos , Animais , Ratos Endogâmicos SHR , Captopril/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Pressão Sanguínea , Hipertensão/tratamento farmacológico , Hipotálamo , Aminopeptidases , Lobo Frontal
4.
Artigo em Inglês | MEDLINE | ID: mdl-37372667

RESUMO

This study was designed to advance our understanding of how feelings of empowerment in people living with dementia still residing at home can be promoted. We conducted qualitative interviews with 12 participants with mild-to-moderate stages of dementia in Germany and Spain as part of a European study on mindful design for dementia. A qualitative thematic content analysis was performed to elicit the key features of the experience reported by the interviewees. Three overarching categories were identified: the first category 'experiencing changes in personal life and coping with changes in life' covered losses and coping strategies; the second category 'retaining a sense of usefulness' included social participation and the need for activities with others; the third category 'feeling empowered' covered reflections on lifetime achievements, accomplishments in the present life, being in control and self-worth. Participants placed a strong emphasis on continuity and on the importance of making active decisions and meaningful social contributions. Empowerment within the person living with dementia was achieved through their interactions with their social environment, including the significance of communication about their needs and wishes and enabling shared decision-making and interactions with others in reciprocity.


Assuntos
Demência , Meio Social , Humanos , Emoções , Tomada de Decisões , Participação Social , Pesquisa Qualitativa , Cuidadores
5.
Int J Mol Sci ; 24(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37373139

RESUMO

Breast cancer (BC) is a leading cause of cancer-related deaths among women worldwide. Neoadjuvant therapy (NAT) is increasingly being used to reduce tumor burden prior to surgical resection. However, current techniques for assessing tumor response have significant limitations. Additionally, drug resistance is commonly observed, raising a need to identify biomarkers that can predict treatment sensitivity and survival outcomes. Circulating microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and have been shown to play a significant role in cancer progression as tumor inducers or suppressors. The expression of circulating miRNAs has been found to be significantly altered in breast cancer patients. Moreover, recent studies have suggested that circulating miRNAs can serve as non-invasive biomarkers for predicting response to NAT. Therefore, this review provides a brief overview of recent studies that have demonstrated the potential of circulating miRNAs as biomarkers for predicting the clinical response to NAT in BC patients. The findings of this review will strengthen future research on developing miRNA-based biomarkers and their translation into medical practice, which could significantly improve the clinical management of BC patients undergoing NAT.


Assuntos
Neoplasias da Mama , MicroRNA Circulante , MicroRNAs , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , MicroRNA Circulante/genética , MicroRNA Circulante/uso terapêutico , Terapia Neoadjuvante , Biomarcadores Tumorais/genética , MicroRNAs/metabolismo
6.
Cell Rep ; 42(5): 112486, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37149868

RESUMO

Recent studies have revealed the heterogeneous nature of astrocytes; however, how diverse constituents of astrocyte-lineage cells are regulated in adult spinal cord after injury and contribute to regeneration remains elusive. We perform single-cell RNA sequencing of GFAP-expressing cells from sub-chronic spinal cord injury models and identify and compare with the subpopulations in acute-stage data. We find subpopulations with distinct functional enrichment and their identities defined by subpopulation-specific transcription factors and regulons. Immunohistochemistry, RNAscope experiments, and quantification by stereology verify the molecular signature, location, and morphology of potential resident neural progenitors or neural stem cells in the adult spinal cord before and after injury and uncover the populations of the intermediate cells enriched in neuronal genes that could potentially transition into other subpopulations. This study has expanded the knowledge of the heterogeneity and cell state transition of glial progenitors in adult spinal cord before and after injury.


Assuntos
Neuroglia , Traumatismos da Medula Espinal , Humanos , Traumatismos da Medula Espinal/genética , Astrócitos , Neurônios , Medula Espinal , Análise de Sequência de RNA
7.
NPJ Parkinsons Dis ; 9(1): 54, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024536

RESUMO

Neurodegeneration with brain iron accumulation (NBIA) represents a group of neurodegenerative disorders characterized by abnormal iron accumulation in the brain. In Parkinson's Disease (PD), iron accumulation is a cardinal feature of degenerating regions in the brain and seems to be a key player in mechanisms that precipitate cell death. The aim of this study was to explore the genetic and genomic connection between NBIA and PD. We screened for known and rare pathogenic mutations in autosomal dominant and recessive genes linked to NBIA in a total of 4481 PD cases and 10,253 controls from the Accelerating Medicines Partnership Parkinsons' Disease Program and the UKBiobank. We examined whether a genetic burden of NBIA variants contributes to PD risk through single-gene, gene-set, and single-variant association analyses. In addition, we assessed publicly available expression quantitative trait loci (eQTL) data through Summary-based Mendelian Randomization and conducted transcriptomic analyses in blood of 1886 PD cases and 1285 controls. Out of 29 previously reported NBIA screened coding variants, four were associated with PD risk at a nominal p value < 0.05. No enrichment of heterozygous variants in NBIA-related genes risk was identified in PD cases versus controls. Burden analyses did not reveal a cumulative effect of rare NBIA genetic variation on PD risk. Transcriptomic analyses suggested that DCAF17 is differentially expressed in blood from PD cases and controls. Due to low mutation occurrence in the datasets and lack of replication, our analyses suggest that NBIA and PD may be separate molecular entities.

8.
J Neurotrauma ; 40(9-10): 883-900, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36178348

RESUMO

Chronic, often intractable, pain is caused by neuropathic conditions such as traumatic peripheral nerve injury (PNI) and spinal cord injury (SCI). These conditions are associated with alterations in gene and protein expression correlated with functional changes in somatosensory neurons having cell bodies in dorsal root ganglia (DRGs). Most studies of DRG transcriptional alterations have utilized PNI models where axotomy-induced changes important for neural regeneration may overshadow changes that drive neuropathic pain. Both PNI and SCI produce DRG neuron hyperexcitability linked to pain, but contusive SCI produces little peripheral axotomy or peripheral nerve inflammation. Thus, comparison of transcriptional signatures of DRGs across PNI and SCI models may highlight pain-associated transcriptional alterations in sensory ganglia that do not depend on peripheral axotomy or associated effects such as peripheral Wallerian degeneration. Data from our rat thoracic SCI experiments were combined with meta-analysis of published whole-DRG RNA-seq datasets from prominent rat PNI models. Striking differences were found between transcriptional responses to PNI and SCI, especially in regeneration-associated genes (RAGs) and long noncoding RNAs (lncRNAs). Many transcriptomic changes after SCI also were found after corresponding sham surgery, indicating they were caused by injury to surrounding tissue, including bone and muscle, rather than to the spinal cord itself. Another unexpected finding was of few transcriptomic similarities between rat neuropathic pain models and the only reported transcriptional analysis of human DRGs linked to neuropathic pain. These findings show that DRGs exhibit complex transcriptional responses to central and peripheral neural injury and associated tissue damage. Although only a few genes in DRG cells exhibited similar changes in expression across all the painful conditions examined here, these genes may represent a core set whose transcription in various DRG cell types is sensitive to significant bodily injury, and which may play a fundamental role in promoting neuropathic pain.


Assuntos
Neuralgia , Traumatismos da Medula Espinal , Ratos , Humanos , Animais , Gânglios Espinais/metabolismo , Neuralgia/genética , Neuralgia/metabolismo , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Neurônios/metabolismo
9.
Front Cell Dev Biol ; 10: 884748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353512

RESUMO

Neurodegenerative diseases affect millions of people worldwide and there are currently no cures. Two types of common neurodegenerative diseases are Alzheimer's (AD) and Parkinson's disease (PD). Single-cell and single-nuclei RNA sequencing (scRNA-seq and snRNA-seq) have become powerful tools to elucidate the inherent complexity and dynamics of the central nervous system at cellular resolution. This technology has allowed the identification of cell types and states, providing new insights into cellular susceptibilities and molecular mechanisms underlying neurodegenerative conditions. Exciting research using high throughput scRNA-seq and snRNA-seq technologies to study AD and PD is emerging. Herein we review the recent progress in understanding these neurodegenerative diseases using these state-of-the-art technologies. We discuss the fundamental principles and implications of single-cell sequencing of the human brain. Moreover, we review some examples of the computational and analytical tools required to interpret the extensive amount of data generated from these assays. We conclude by highlighting challenges and limitations in the application of these technologies in the study of AD and PD.

10.
Int J Mol Sci ; 23(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36233303

RESUMO

Lysosomal dysfunction has been proposed as one of the most important pathogenic molecular mechanisms in Parkinson disease (PD). The most significant evidence lies in the GBA gene, which encodes for the lysosomal enzyme ß-glucocerebrosidase (ß-GCase), considered the main genetic risk factor for sporadic PD. The loss of ß-GCase activity results in the formation of α-synuclein deposits. The present study was aimed to determine the activity of the main lysosomal enzymes and the cofactors Prosaposin (PSAP) and Saposin C in PD and healthy controls, and their contribution to α-synuclein (α-Syn) aggregation. 42 PD patients and 37 age-matched healthy controls were included in the study. We first analyzed the ß-GCase, ß-galactosidase (ß-gal), ß-hexosaminidase (Hex B) and Cathepsin D (CatD) activities in white blood cells. We also measured the GBA, ß-GAL, ß-HEX, CTSD, PSAP, Saposin C and α-Syn protein levels by Western-blot. We found a 20% reduced ß-GCase and ß-gal activities in PD patients compared to controls. PSAP and Saposin C protein levels were significantly lower in PD patients and correlated with increased levels of α-synuclein. CatD, in contrast, showed significantly increased activity and protein levels in PD patients compared to controls. Increased CTSD protein levels in PD patients correlated, intriguingly, with a higher concentration of α-Syn. Our findings suggest that lysosomal dysfunction in sporadic PD is due, at least in part, to an alteration in Saposin C derived from reduced PSAP levels. That would lead to a significant decrease in the ß-GCase activity, resulting in the accumulation of α-syn. The accumulation of monohexosylceramides might act in favor of CTSD activation and, therefore, increase its enzymatic activity. The evaluation of lysosomal activity in the peripheral blood of patients is expected to be a promising approach to investigate pathological mechanisms and novel therapies aimed to restore the lysosomal function in sporadic PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Catepsina D/genética , Catepsina D/metabolismo , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Hexosaminidase B/genética , Hexosaminidase B/metabolismo , Humanos , Lisossomos/metabolismo , Mutação , Doença de Parkinson/metabolismo , Saposinas/genética , Saposinas/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , beta-Galactosidase/metabolismo , beta-N-Acetil-Hexosaminidases/metabolismo
11.
Biomedicines ; 10(10)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36289718

RESUMO

Brain dopamine, in relation to the limbic system, is involved in cognition and emotion. These functions are asymmetrically processed. Hypertension not only alters such functions but also their asymmetric brain pattern as well as their bilateral pattern of neurovisceral integration. The central and peripheral renin-angiotensin systems, particularly the aminopeptidases involved in its enzymatic cascade, play an important role in blood pressure control. In the present study, we report how these aminopeptidases from left and right cortico-limbic locations, plasma and systolic blood pressure interact among them in spontaneously hypertensive rats (SHR) unilaterally depleted of dopamine. The study comprises left and right sham and left and right lesioned (dopamine-depleted) rats as research groups. Results revealed important differences in the bilateral behavior comparing sham left versus sham right, lesioned left versus lesioned right, and sham versus lesioned animals. Results also suggest an important role for the asymmetrical functioning of the amygdala in cardiovascular control and an asymmetrical behavior in the interaction between the medial prefrontal cortex, hippocampus and amygdala with plasma, depending on the left or right depletion of dopamine. Compared with previous results of a similar study in Wistar-Kyoto (WKY) normotensive rats, the asymmetrical behaviors differ significantly between both WKY and SHR strains.

12.
Front Cell Dev Biol ; 10: 1001701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313573

RESUMO

Neural induction, both in vivo and in vitro, includes cellular and molecular changes that result in phenotypic specialization related to specific transcriptional patterns. These changes are achieved through the implementation of complex gene regulatory networks. Furthermore, these regulatory networks are influenced by epigenetic mechanisms that drive cell heterogeneity and cell-type specificity, in a controlled and complex manner. Epigenetic marks, such as DNA methylation and histone residue modifications, are highly dynamic and stage-specific during neurogenesis. Genome-wide assessment of these modifications has allowed the identification of distinct non-coding regulatory regions involved in neural cell differentiation, maturation, and plasticity. Enhancers are short DNA regulatory regions that bind transcription factors (TFs) and interact with gene promoters to increase transcriptional activity. They are of special interest in neuroscience because they are enriched in neurons and underlie the cell-type-specificity and dynamic gene expression profiles. Classification of the full epigenomic landscape of neural subtypes is important to better understand gene regulation in brain health and during diseases. Advances in novel next-generation high-throughput sequencing technologies, genome editing, Genome-wide association studies (GWAS), stem cell differentiation, and brain organoids are allowing researchers to study brain development and neurodegenerative diseases with an unprecedented resolution. Herein, we describe important epigenetic mechanisms related to neurogenesis in mammals. We focus on the potential roles of neural enhancers in neurogenesis, cell-fate commitment, and neuronal plasticity. We review recent findings on epigenetic regulatory mechanisms involved in neurogenesis and discuss how sequence variations within enhancers may be associated with genetic risk for neurological and psychiatric disorders.

13.
Int J Mol Sci ; 23(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35805938

RESUMO

Mutations in LRRK2 and GBA1 are key contributors to genetic risk of developing Parkinson's disease (PD). To investigate how LRRK2 kinase activity interacts with GBA and contributes to lysosomal dysfunctions associated with the pathology of PD. The activity of the lysosomal enzyme ß-Glucocerebrosidase (GCase) was assessed in a human neuroglioma cell model treated with two selective inhibitors of LRKK2 kinase activity (LRRK2-in-1 and MLi-2) and a GCase irreversible inhibitor, condutirol-beta-epoxide (CBE), under 24 and 72 h experimental conditions. We observed levels of GCase activity comparable to controls in response to 24 and 72 h treatments with LRRK2-in-1 and MLi-2. However, GBA protein levels increased upon 72 h treatment with LRRK2-in-1. Moreover, LC3-II protein levels were increased after both 24 and 72 h treatments with LRRK2-in-1, suggesting an activation of the autophagic pathway. These results highlight a possible regulation of lysosomal function through the LRRK2 kinase domain and suggest an interplay between LRRK2 kinase activity and GBA. Although further investigations are needed, the enhancement of GCase activity might restore the defective protein metabolism seen in PD.


Assuntos
Glucosilceramidase , Doença de Parkinson , Linhagem Celular , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Glioma/metabolismo , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Humanos , Inositol/análogos & derivados , Inositol/farmacologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Mutação , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
14.
Emerg Infect Dis ; 28(4): 841-843, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35318929

RESUMO

Sporadic Legionnaires' disease is frequently detected in commercial truck drivers. We report 2 sporadic cases of this disease in Barcelona, Spain, that occurred during December 2019 and September 2020. Laboratory findings were consistent with windshield wiper fluid without added screen wash as a possible source of infection for both cases.


Assuntos
Doença dos Legionários , Veículos Automotores , Humanos , Doença dos Legionários/diagnóstico , Doença dos Legionários/epidemiologia , Espanha/epidemiologia
15.
J Aging Stud ; 60: 100995, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35248311

RESUMO

Receiving a dementia diagnosis is a difficult experience for most people and often affects their wellbeing negatively. To support people's wellbeing, in a therapeutic context, life-storytelling, reminiscence and mindfulness are used with people with dementia. In an everyday context, traditional games are used as a resource for stimulating memory, cognition and social activity. While an increasing number of creative strategies are available to support people with dementia, the area of board games design and their effect on wellbeing is underexplored. This paper reports on the evaluation of the This is Me (TIM) mindful life-storytelling board game by the European project MinD. Using a co-design methodology, TIM was developed with and for people with mild to moderate dementia to support their wellbeing by enhancing self-empowerment and social engagement. A focus group methodology was used to evaluate TIM with 50 people with dementia and 19 carers across four countries. TIM was evaluated with regard to the usability and experience of the design as well as people's emotional wellbeing, social engagement and agency. The thematic analysis demonstrated that the combination of life-storytelling and mindfulness allowed players to engage in meaningful social interaction and, as a result, they reported enjoyment, learning, more acceptance of the past and present situation, and that they perceived looking forward into the future together with others as helpful. The study demonstrates that design can be a useful means to support people with dementia in aspects of emotional wellbeing, social engagement and a sense of agency.


Assuntos
Demência , Atenção Plena , Cuidadores/psicologia , Comunicação , Demência/psicologia , Humanos , Participação Social
16.
Biomedicines ; 10(2)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35203536

RESUMO

In emotional processing, dopamine (DA) plays an essential role, and its deterioration involves important consequences. Under physiological conditions, dopamine exhibits brain asymmetry and coexists with various neuropeptides that can coordinate the processing of brain functions. Brain asymmetry can extend into a broader concept of asymmetric neurovisceral integration, including behavior. The study of the activity of neuropeptide regulatory enzymes (neuropeptidases, NPs) is illustrative. We have observed that the left and right brain areas interact intra- and inter-hemispherically, as well as with peripheral tissues or with physiological parameters such as blood pressure or with behaviors such as turning preference. To obtain data that reflect this integrative behavior, we simultaneously analyzed the impact of left or right brain DA depletion on the activity of various NPs in corticolimbic regions of the left and right hemispheres, such as the medial prefrontal cortex, amygdala and hippocampus, as well as on the plasma activity of the same aminopeptidase activities (APs) and on systolic blood pressure (SBP). Intra- and inter-hemispheric interactions as well as the interactions of NPs from the left or right hemispheres were analyzed with the same plasma APs and the SBP obtained from sham and from left or right lesioned rats. The results demonstrate a complex profile depending on the hemisphere considered. They definitively confirm an asymmetric neurovisceral integration and reveal a higher level of inter-hemispheric corticolimbic interactions including with SBP after left dopamine depletion.

17.
Sci Rep ; 11(1): 16977, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417498

RESUMO

Chromatin architecture influences transcription by modulating the physical access of regulatory factors to DNA, playing fundamental roles in cell identity. Studies on dopaminergic differentiation have identified coding genes, but the relationship with non-coding genes or chromatin accessibility remains elusive. Using RNA-Seq and ATAC-Seq we profiled differentially expressed transcripts and open chromatin regions during early dopaminergic neuron differentiation. Hierarchical clustering of differentially expressed genes, resulted in 6 groups with unique characteristics. Surprisingly, the abundance of long non-coding RNAs (lncRNAs) was high in the most downregulated transcripts, and depicted positive correlations with target mRNAs. We observed that open chromatin regions decrease upon differentiation. Enrichment analyses of accessibility depict an association between open chromatin regions and specific functional pathways and gene-sets. A bioinformatic search for motifs allowed us to identify transcription factors and structural nuclear proteins that potentially regulate dopaminergic differentiation. Interestingly, we also found changes in protein and mRNA abundance of the CCCTC-binding factor, CTCF, which participates in genome organization and gene expression. Furthermore, assays demonstrated co-localization of CTCF with Polycomb-repressed chromatin marked by H3K27me3 in pluripotent cells, progressively decreasing in neural precursor cells and differentiated neurons. Our work provides a unique resource of transcription factors and regulatory elements, potentially involved in the acquisition of human dopaminergic neuron cell identity.


Assuntos
Diferenciação Celular/genética , Cromatina/metabolismo , Neurônios Dopaminérgicos/citologia , Células-Tronco Embrionárias Humanas/citologia , Transcriptoma/genética , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Motivos de Nucleotídeos/genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA-Seq , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcrição Gênica
18.
BMC Biol ; 19(1): 132, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172044

RESUMO

BACKGROUND: Oligodendrocytes, responsible for axon ensheathment, are critical for central nervous system (CNS) development, function, and diseases. OLIG2 is an important transcription factor (TF) that acts during oligodendrocyte development and performs distinct functions at different stages. Previous studies have shown that lncRNAs (long non-coding RNAs; > 200 bp) have important functions during oligodendrocyte development, but their roles have not been systematically characterized and their regulation is not yet clear. RESULTS: We performed an integrated study of genome-wide OLIG2 binding and the epigenetic modification status of both coding and non-coding genes during three stages of oligodendrocyte differentiation in vivo: neural stem cells (NSCs), oligodendrocyte progenitor cells (OPCs), and newly formed oligodendrocytes (NFOs). We found that 613 lncRNAs have OLIG2 binding sites and are expressed in at least one cell type, which can potentially be activated or repressed by OLIG2. Forty-eight of them have increased expression in oligodendrocyte lineage cells. Predicting lncRNA functions by using a "guilt-by-association" approach revealed that the functions of these 48 lncRNAs were enriched in "oligodendrocyte development and differentiation." Additionally, bivalent genes are known to play essential roles during embryonic stem cell differentiation. We identified bivalent genes in NSCs, OPCs, and NFOs and found that some bivalent genes bound by OLIG2 are dynamically regulated during oligodendrocyte development. Importantly, we unveiled a previously unknown mechanism that, in addition to transcriptional regulation via DNA binding, OLIG2 could self-regulate through the 3' UTR of its own mRNA. CONCLUSIONS: Our studies have revealed the missing links in the mechanisms regulating oligodendrocyte development at the transcriptional level and after transcription. The results of our research have improved the understanding of fundamental cell fate decisions during oligodendrocyte lineage formation, which can enable insights into demyelination diseases and regenerative medicine.


Assuntos
Oligodendroglia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/genética
19.
Cell Rep ; 34(5): 108721, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33535036

RESUMO

Spinal cord injury (SCI) is one of the most devastating neural injuries without effective therapeutic solutions. Astrocytes are the predominant component of the scar. Understanding the complex contributions of reactive astrocytes to SCI pathophysiologies is fundamentally important for developing therapeutic strategies. We have studied the molecular changes in the injury environment and the astrocyte-specific responses by astrocyte purification from injured spinal cords from acute to chronic stages. In addition to protein-coding genes, we have systematically analyzed the expression profiles of long non-coding RNAs (lncRNAs) (>200 bp), which are regulatory RNAs that play important roles in the CNS. We have identified a highly conserved lncRNA, Zeb2os, and demonstrated using functional assays that it plays an important role in reactive astrogliosis through the Zeb2os/Zeb2/Stat3 axis. These studies provide valuable insights into the molecular basis of reactive astrogliosis and fill the knowledge gap regarding the function(s) of lncRNAs in astrogliosis and SCI.


Assuntos
Astrócitos/metabolismo , Gliose/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Humanos , Camundongos , Traumatismos da Medula Espinal/fisiopatologia
20.
Exp Biol Med (Maywood) ; 246(6): 695-706, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33148012

RESUMO

Hyperoxia-hypoxia exposure is a proposed cause of alveolar developmental arrest in bronchopulmonary dysplasia in preterm infants, where mitochondrial reactive oxygen species and oxidative stress vulnerability are increased. The aryl hydrocarbon receptor (AhR) is one of the main activators of the antioxidant enzyme system that protects tissues and systems from damage. The present study aimed to determine if the activation of the AhR signaling pathway by prenatal administration of indole-3-carbinol (I3C) protects rat pups from hyperoxia-hypoxia-induced lung injury. To assess the activation of protein-encoding genes related to the AhR signaling pathway (Cyp1a1, Cyp1b1, Ugt1a6, Nqo1, and Gsta1), pup lungs were excised at 0, 24, and 72 h after birth, and mRNA expression levels were quantified by reverse transcription-quantitative polymerase chain reaction assays (RT-qPCR). An adapted Ratner's method was used in rats to evaluate radial alveolar counts (RACs) and the degree of fibrosis. The results reveal that the relative expression of AhR-related genes in rat pups of prenatally I3C-treated dams was significantly different from that of untreated dams. The RAC was significantly lower in the hyperoxia-hypoxia group (4.0 ± 1.0) than that in the unexposed control group (8.0 ± 2.0; P < 0.01). When rat pups of prenatally I3C-treated dams were exposed to hyperoxia-hypoxia, an RAC recovery was observed, and the fibrosis index was similar to that of the unexposed control group. A cytokine antibody array revealed an increase in the NF-κB signaling cascade in I3C-treated pups, suggesting that the pathway could regulate the inflammatory process under the stimulus of this compound. In conclusion, the present study demonstrates that I3C prenatal treatment activates AhR-responsive genes in pup's lungs and hence attenuates lung damage caused by hyperoxia-hypoxia exposure in newborns.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Displasia Broncopulmonar/genética , Indóis/administração & dosagem , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/genética , Efeitos Tardios da Exposição Pré-Natal/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/complicações , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fibrose , Hiperóxia/complicações , Hiperóxia/genética , Hipóxia/complicações , Hipóxia/genética , Indóis/uso terapêutico , Mediadores da Inflamação/metabolismo , Pulmão/patologia , Lesão Pulmonar/complicações , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Aumento de Peso
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